It is known in the art that various skin conditions can be treated, improved, and/or prevented by reducing release of endogenous acetylcholine (e.g., through administration of inhibitors of release, such as botulinum). For example, see Suskind (2007) for the use of botulinum to treatment of acne or Sanders (2007) for the use of botulinum to treat excess sebum production, seborrhea, sebaceous hyperplasia, seborrhoeic dermatitis. See also Shah (2008), Li (2013) and Rose (2013) for the use of botulinum to treat excess sebum production and enlarged pore size. Other skin conditions that may benefit from treatment with botulinum (i.e., from treatment with an inhibitor of acetylcholine release) include, for example, rosacea (See Sanders (2012), psoriasis (Zanchi (2008)) and/or lichen simplex (Heckmann (2002)).
A recent publication confirms that nicotinic receptors may modulate sebum production (See Li (2103)). However, neither this publication nor other current reviews of the field of treating highly prevalent diseases such as acne, where excess sebum production is well known to be a key part of disease pathogenesis (See Zanglein (2008), Kurokawa (2009), Bellew (2011), and Fulton (2013)), specifically teach or suggest use of acetylcholine receptor antagonists. At least one reason that researchers and/or reviewers might not have previously suggested such strategies is due to the above-noted understanding that such agents as nicotinic receptor antagonists cause significant skin damage.
The skin damage known to be caused by nicotinic acetylcholine receptor antagonists, thought to render them unsuitable for use as agents to treat skin conditions, includes, for example, acantholysis. Please see Kurzen (2006). Acantholysis is the separation of individual epidermal keratinocytes from their neighbor, as in conditions such as pemphigus vulgaris. It is also described as the loss of intercellular connections, such as desmosomes, resulting in loss of cohesion between keratinocytes, again as seen in diseases such as pemphigus vulgaris. Clinical presentations of acantholysis include but are not limited to the appearance of blisters, pruritic eruptions, papules, acneiform lesions, vesicles, pustules, and/or bullous lesions.